Tracking and Treating Toxic Waste
inUrban NeighborhoodsNew Center Will Study Risks and Provide Tools
to Help Clean Polluted City Sites

Abandoned factories and contaminated soil can stall
efforts to revive blighted urban neighborhoods. That's
because city officials, developers and nearby residents
often share common concerns: Is it safe to rebuild here?
Will workers and residents become ill from toxic materials
that escape into the air and water supplies?

A new research center, led by engineers and scientists
at The Johns Hopkins University, plans to address these
fears by creating new tools to gauge risks associated with
hazardous waste sites and by developing new ways to clean up
harmful pollutants. The U.S. Environmental Protection Agency
recently approved a
five-year $5.2 million grant to launch this new
Center for
Hazardous Substances in Urban Environments, based at
Johns Hopkins. The funds will support research and allow
center participants to provide technical help to community
groups, state, municipal and local environmental regulators
and industry representatives in the Northeast. Researchers
from four other institutions--the University of Maryland,
Morgan State University, the University of Connecticut and
the New Jersey Institute of Technology--will participate in
the new center and share in the EPA grant.

"Before we applied for this grant, we asked regional
EPA officials about the most serious challenges they faced,"
said
Ed Bouwer, a Johns Hopkins
professor of geography and
environmental engineering who serves as the center's
director. "One of the top issues they mentioned was urban
livability--making sure that people in cities have air,
water and soil that will not expose them to toxic
substances. The other big issue was brownfields--abandoned
lots and buildings that may contain hazardous materials. If
you can redevelop these properties, you can create jobs and
improve the tax base. So the cities and states have an
economic incentive to promote new construction on the
brownfields if the environmental concerns can be
addressed."

Ed Bouwer, right, and Hedy Alavi are serving as
director and associate director, respectively, of
the new Center for Hazardous Substances in Urban
Environments.All photos by Jay Van Rensselaer

That's where the new center comes in. Bouwer and his
colleagues are developing new tests and computer models to
identify chemicals that are present on blighted sites and
determine whether they are spreading away from the sites
through rainfall runoff or aboard windswept dust particles.
These new tracking methods should help local officials,
developers and community leaders decide on the best way to
remove or neutralize the hazardous wastes. In some cases,
the researchers may conclude that the Earth's natural self-
cleansing process will eliminate the hazard if the property
is merely left alone for a specified period of time.

"We're creating tools to help assess these waste sites,
so that we can determine how much of a problem really exists
at each one," Bouwer said. "Determining the relative risks
will help us decide the best way to manage that site."

Isam Sabbah, a Johns Hopkins postdoctoral fellow affiliated
with the new research center, uses lab equipment to
study how pollutants move through sediment.

Under the auspices of the center, Johns Hopkins faculty
members are pursuing four new research projects:

Marc Parlange,
professor of geography and environmental engineering, and
Charles Meneveau, professor of
mechanical engineering,
are leading a team that will use LIDAR, a variation of radar
that uses light instead of radio waves, to identify airborne
pollutants and track their movement through an urban
atmosphere.

Bouwer and
Bill Ball, professor of geography and environmental
engineering,
are developing a method to determine how quickly buried
pollutants move through the soil as a result of rainfall
infiltration and groundwater flow.

Alan Stone and
Charles O'Melia, professors of geography and environmental
engineering, are developing a new test to measure the
toxicity and mobility of chromium at a waste site.

Doctoral student Rich Carbonaro employs a capillary
electrophoresis machine to identify the chemical
form of chromium in his sample, as his advisor,
Alan Stone, looks on. Stone and colleagues are
developing a new test to measure the toxicity
and mobility of chromium at waste sites.

Lynn Roberts,
associate professor of geography and environmental
engineering, and Howard Fairbrother,
assistant professor of
chemistry, are devising a new filter
that can turn toxic vapors vacuumed out of a waste site into
a harmless mixture of salt, water and carbon dioxide.

The center will devote 30 percent of its budget to
outreach activities, providing information to the
regulators, consultants and citizens who will help decide
the future of urban hazardous waste sites. In his role as
associate director of the new center,
Hedy Alavi, a
geography and environmental engineering lecturer, will
supervise the outreach program.

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